Polymer of 1,4-bis-(tris-(nf2)methoxy) 2-butene oxide



3,441,520 POLYMER F 1,d-EHS-[TRllS-(NFQMETHQXYl Z-BUTENE QXIDE David S.Bosniack, New York, N.Y., and Eugene L.

'tes aten tonitrile, and 12 g. of perfiuoroguanidine. The reaction wasstirred at room temperature overnight. After removal of the unreactedgases a 35% F /N stream was passed over the surface of the acetonitrilesolution for 4.5 hours. During the fluorination the temperature in thereactor to n Fords and Joel G. Her er Elizabeth 5 o l inl f as signorsto Esso Research 215d Engineering ig i at E Company, a corporation of Dl or Stripping o the acetonitrile the viscous residue N0 Drawing FiledJuly 29, 1954, s No' 386,087 was dissolved in Freon 113 or CCL; anddried with an- Knt CL e 13/00 hydrous Na CO The solution Was filteredand the solvent US. Cl. 260--2 6 Claim 10 blown off. The residue wasplaced on a silica gel column (the silica gel had previously beentreated with caustic,

This invention relates to the synthesis of solid poly- H 0, and dried at600 F. for 6 hours) with a minimum -mers from 1,4bis-[tris-(NF)methoxy]-2-butene oxide amount of CCl Elution with CCL, gave 7.9 g.(74% by the use of certain catalysts, such as particularly antiyield) ofcis-1,4-bis[tris-(NF )methoxy]-2 butene oxide mony pentachloride andantimony pentafluoride, which having apurity of 96+%. make thepreparation efficient and make the solid polymer Calculated for C H O NF C, 16.45 N, 19.18; F, product more valuable, especially for use insolid rocket 52.03. Found: C, 16.88; N, 19.31; F, 53.30. propellantformulations. It is concerned with providing The trans isomer of I wasprepared by the basic hysuch solid polymers of high melting points andwhich drolysis of commercially available trans 1,4-dichloro 2- showcrystallinity. butene followed by epoxidation.

The high-energy epoxide monomer used for the polym- To make the productIV having a trans structure from erization contains one NF group percarbon atom and the trans isomer of compound I, the procedure describedhas the structural formula: in Example 2 was followed,

(NF2)1COCHz-CHCH-CHzOC(NFz)3 Example 2.Trans-1,4-bis-[tris(NF)methoxy]-2- This compound is referred to herein as FABDE. It is thebutene oxlde fiuorinated erfluoroguanidine adduct of 1,4-dihydroxy-2-butene oxid either as the cis or trans isomer. The prep- A Pressurereactor was Charged with of trans aration of the monomeric FABDE andvarious ways in L4'dlllydmxy'z'butene oxlde, 0026 l 6 of which it ispolymerized or modified more generally, are acetonitrile and 1.788 g. ofperfiuoroguanidine. The reacdescribed in s application 3 03 fil d b tionmixture was stirred at room temperature overnight. E. L. Stogryn, J. G.Berger and L. I. Engel on July 29, After removal of the unreacted gasesa 10% F /N 1964. The synthesis route for obtaining FABDE is given streamwas passed over the surface of the reaction mixas follows: ture for 2hours at 0 C.

Working up the reaction product in a manner similar to What wasdescribed in Example 1 yielded 1.4 g. (74% HO CHPCH7CH-CHZOH 2 (EZNF oftrans-1,4-bis[tris(NF )methoxy]-2-butene oxide hav- 0 NFZ ing a purityof 90%.

1 II Calculated for C H O N F C, 16.45; N, 19.18; F, NFZ NFZ 52.03.Found: C, 16.95; N, 19.17;F, 53.4.

I l HNF-O-0 CHr-CH-CHOH20C-IINF The infrared and proton spectrum areconsistent with NFZ llTFz the structure IV in the trans configuration.

III The high NF content (71%) and the reaction prop- NFz z erties of theepoxide function in the FABDE monomer B adapts it for use as a liquidenergetic oxidizer or as an i intermediate in the synthesis of usefulsolid polymers that NFQ 0 NF2 IV are suitable components for advancedsolid propellant formulations. In making the high NF content epoxides Inthe Synthesis, {ha Starting Teactant I is Y Y- and in polymerizing theseepoxides, it is important to 2-butene oxide. The perfiuoroguanidinereactant is II, and preserve the 2 content f the resulting polymers andthe addllct is In, and thefiuonnated adduct to make the polymerizationto take place in such a man- The 91S 150m? P l=4dlhydroxyfz'butene Oxldel net as to produce consistent polymers having the base plu'ed byepoxldanon commejrclany avallable C15 properties with respect to thermalstability, compatibility dlhydroxy'z'blitene' Using the lsomer thereactant with other propellant components, good handling charfPreParatmn m i i i g fi fis tha acteristics and desired solidcharacteristics such as cryszif fg nng are 15 descn e In t e Oextallinity, and uniform high melting point.

p Other solid N1 oxidizers, based on perfluoroguanidine Examplel-"preparatlon of 1=4jb1s'[mS(NF2) chemistry which are energeticallyclose to FABDE polymethoxy]'z'butene OXlde mers are known. However, asthe following Table I il- A pressure reactor was charged with 2.52 g. ofcis-l,4- lustrates, none of these NF oxidizers is as good aspolydihydroxy-Z-butene oxide, 0.168 g. urea, 30 ml. of ace- FABDE.

TABLE I Poly- FABDE FA-NGI Info-635 1 FA-PO K Tetryl Vacuum thermalstability, co./g./l00 hours at C 2. 3 4. 0 10. 3 6. 7 at 60 Impactsensitivity, Kg-cm 35 5 15 2, 5 33 Thermogravametric analysis, C. iorwt. loss to start 84 191 75-100 Auto-ignition temperature, C 253 234 231219 249 3 [(NF2)3COCH213PO. 4 Commercial explosive (non-NIH).

In accordance with the present invention a significant discovery andadvance in the development of solid FABDE polymers was made in findingthat the halides of antimony, in particular antimony pentachloride andantimony 4 activity of the SbCl and SbF catalyst during polymerizationof the FTBDE monomer, it was observed that low catalyst concentrationstend to favor the formation of the desired solid polymers as shown inthe following results:

pentafluoride, are uniquely superior to other catalysts for thepolymerization of FABDE monomers to solid polymers. Using thesecatalysts, methods were also devised for controlling the stericregularity of polymerization. The degree of orderliness or *regularityof the ring opening polymerization, catalyzed by the antimony halides,is discernible by chemical and instrumental techniques, e.g.,

Examples 810.-No solvent polymerization The FABDE monomer was charged toa polymerization vessel and sealed with a serum cap and placed in a 0 C.bath. While the monomer was stirring the catalyst was injected throughthe serum cap with a hypodermic needle and the polymerization wasallowed to proceed for solubility and powder X-ray diagrams. Thefollowing exthe time period described in Table IV amples illustrate thetechnique we have developed for controlling the degree of conversion tosolid polymer and the degree of crystallinity of the solid polymer.

EXAMPLE 3 The cis FABDE monomer of at least 96% purity was charged in anamount of 0.80 g. into Freon 113 (F CClCCl F) to obtain a solution ofthe monomer in the solvent. The SbCl catalyst was added in proportionsof 0.4 mole percent, based on the monomer in the solution which wascooled to 22 C. in a reactor. The solution containing the admixedcatalyst was stirred for one hour, then the polymerization mixture wasallowed to stand for 18 hours at 22 C.

The final polymerization mass was allowed to warm up to 25 C. thesolvent was pumped off and the polymer oils were separated from polymersolids by extracting the oils with small portions of methylene chloride.After vacuum drying the solid polymer, a White powder was obtained andanalyzed. The white powder had melting points in the range of 198 to ashigh as 207 C.

The cis FABDE monomer gave solid polymer by this procedure inconversions as high as 85 to 90%. This polymer is soluble in Freon 113and has a degree of crystallinity of 1 to 5% by X-ray measurements.

The following is a typical chemical analysis:

TABLE II Theory Found A r l sis:

l ercent O 16. 45 15. 82 Percent N 19. 18 19. 44 Percent F 52. 03 52. 8

The solid polymer is shown by analysis to have a composition of therecurring monomeric unit:

NFz NF; 1 OOH(OH2O 7NFz)OH(CHzO( NFz)- L l lFz 11115: .1 Examples 4-7.Influence of solvent and catalyst concentration Studies have shown thatthe solid polymers of FABDE may be mixed with other propellantingredients such as NF containing liquid organic plasticizers, e.g.,hexakis (NP )dipropyl ether, powdered metal fuels such as boron,aluminum, various inorganic oxidizers such as ammonium perchlorate,hydrazine diperchlorate, and other substances which may have aprotective coating such as lithium and nitronium perchlorate.Formulations using the solid polymers of FABDE has Isp values in therange of 290 to above 305 with the advantage that the solid polymer canbe present in a high proportion as shown in the following formulationswith solid FABDE polymer:

There is an advantage in being able to use a large amount of solidpolymer as binder to increase the strength of the propellant composite,however, even the liquid FABDE polymers may be used to a certain extentfor blending and filling in voids between solid particles. The solidpolymers showing crystallinity tend to form binders of higher tensilestrength and to form composites of slower burning rate.

The invention described is claimed as follows:

1. A method of preparing crystalline solid polymers of 1,4-bis[tris (NF)methoxy]2 butene oxide monomer which comprises polymerizing saidmonomer with a catalytic action of a catalyst selected from the groupconsisting of SbCl and SbF 2. The method as described in claim 11 inwhich the monomer is polymerized in a polyfluoroalkyl chloride solvent.

3. The method of claim 1, in which the monomer is polymerized free ofsolvent.

4. The method of claim 1, in which the monomer polymerized is a cisisomer.

5. The method of claim 1, in which the monomer polymerized is a transisomer.

6. Solid polymer of 1,4 bis [tris-(NFQmethoxyH- 5 6 butene oxide havingthe composition of the recurring References Cited monomenc Hoffman etal.: Chem. Reviews, vol. 62, pp. 1218 I NFZ IF: I (1962). T 5 LELAND A.SEBASTIAN, Primary Examiner.

NB NF:

US. Cl. X.R.

with melting points above 192 C. and showing X-ray crystallinity. 14919,20, 22, 44; 260348, 584

1. A METHOD OF PREPARING CRYSTALLINE SOLID POLYMERS OF 1,4-BIS(TRI -(NF2)METHOXY)2 - BUTENE OXIDE MONOMER WHICH COMPRISES POLYMERIZING SAIDMONOMER WITH A CATALYTIC ACTION OF A CATALYST SELECTED FROM THE GROUPCONSISTING OF SBCL5 AND SBF5.
 6. SOLID POLYMER OF 1,4 - BIS -(TRIS-(NF2)METHOXY)2BUTENE OXIDE HAVING THE COMPOSITION OF THE RECURRINGMONOMERIC UNIT: